1. Field of Invention
This invention relates to an improved hull design for boats, and particularly for use on a hull for relatively long inboard boats, such as inboard ski boats.
2. Prior Art
It has long been known that, for use in water-skiing and other similar water sports requiring a boat, an inboard boat provides distinct advantages in pulling power, tracking and stability, i.e., having the boat remain relatively flat in turns, over outboard or stern-drive boats. However, there are disadvantages present in conventional inboard boat hulls in that the longer the inboard boat was, the less lift could be achieved. This decreased lift resulted in increased drag, i.e., less fuel efficiency and a reduced speed for a boat with an engine of given horsepower. Also, with inboard boats having conventional hull designs, many required downwardly-extending, fixed tracking fins positioned midship adjacent the keel. These were required to assure proper turning and tracking, i.e., straight-line stability, of the inboard boat. Also, many inboard boats having a so-called relatively "deep Vee" configuration which ran the entire length of the boat suffered from restricted turning ability.
The present invention overcomes the foregoing disadvantages of prior inboard boat hull design by combining a series of respective pairs of strakes, each pair having a specific placement, and a specific longitudinal commencement and termination, with a hull deadrise angle that progressively decreases from bow to stern. Such a gradual transition from an essentially deep-V configuration for the bow of the boat, to an essentially flattened deadrise for the stern of the boat, done in a smooth progression, i.e., smooth transition, over the length of the boat, permits a boat made in accordance with the present invention to provide a smooth ride, such as when entering and cutting through waves by the bow, yet permits maximized speed, stability in turns, and a small wake. The sharp entry deadrise angle of a deep vee hull allows the present inboard to have the good ride characteristics that are present in stern drive and outboard boat hulls, which type boats normally have a constant deadrise from bow to stern.
Further, the general deadrise transition of the present invention coupled with the specific configuration and placement of respective pairs of strake members permits the boat to lift up out of the water, unlike a conventional inboard boat of similar length, and plane with the least amount of wetted surface area required to properly handle the boat. Thus, with a boat made in accordance with the present invention, much less horsepower per pound of hull is required to achieve the same speed as hulls of prior designs.
It is known that an inboard boat becomes very inefficient at higher speeds compared to an outboard or stern-drive boat, i.e., inboard/outboard boat. This is because the propeller cannot be angled to lift the hull out of the water. Thus, to achieve maximum efficiency in a large inboard boat, i.e., one of relatively long length, the hull design had to plane quickly and lift out of the water at higher speeds. Advantageously, the hull design of the present invention permits this to occur by a combination of a variable deadrise angle and the specific placement and configuration of the strakes.
Thus, it is an object of the present invention to provide a hull for a relatively long inboard boat which provides a smooth ride, a reduced wake, improved handling, and maximized speed.
It is a further object of the present invention to provide an inboard boat hull having a gradual, progressive transition in deadrise angle for use in an inboard boat application, without creating any unnecessary drag in the boat as it planes through the water. That is, the smooth transition assures that there is no so-called "hook", i.e., concave area in the bottom of the hull in the wetted surface area when the boat is running, to cause a drag on the hull and reduce the boat's overall performance.
It is yet a further object of the present invention to provide an inboard boat hull which has an improved transition of deadrise angle from bow to stern combined with a series of specially configured and placed pairs of strakes, which combination provides a relatively long inboard boat with a smooth ride yet the handling and speed of a much shorter inboard boat.
The means by which the foregoing and other objects of the present invention are accomplished and the manner of their accomplishment will be readily understood from the following specification upon reference to the accompanying drawings, in which: